Understanding International Relations, Third Edition

Understanding International Relations

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their own power. The result of these movements is the emergence of a bal-
ance of power. The balance of power is the theory of the international sys-
tem. Balances of power can be defined in terms of the number of ‘poles’ in
the balance – the metaphor gets a bit confused here – and the number of
poles is defined by the number of states which can seriously threaten each
other’s basic survival; Waltz argues that this means the system (in 1979) is
bipolar. Only the United States and the USSR have the ability to threaten
each other’s survival. As we will see, most writers on the balance of power
see bipolar balances as inherently unstable, because changes in the capacity
of one actor can only be met by similar changes in the other – and this
process is always likely to get out of sync. Waltz disagrees; according to
him, bipolar systems are easier to manage because there are fewer interested
parties involved.
This is a theory of the structure of the international system, and a good
question would be how structure relates to ‘agency’ – what does it mean to
say that states must behave in certain kinds of ways? Again, how can it be
assumed that a balance of power will always emerge or that states will
be able to manage a bipolar system, given that they do not consciously wish
to create balances – indeed, most states would prefer to eliminate poten-
tially threatening states (that is, all states other than themselves)? Waltz’s
answer to these questions is that there is no actual guarantee that balances
will form or that power management will be successful; however, states that
do not respond to the signals sent to them by the international system, that
is to say states that ignore the distribution of power in the world, will find
that they suffer harm as a result; indeed, under some circumstances, they
could face loss of independence. Since states do not want this to happen the
likelihood is that they will take the necessary steps (Waltz 1979: 118). But
they may not; some states, but not very many in the twentieth century, have
actually lost their independence, while others because of a favourable
geographical position, or some other natural advantage, have the luxury of
being able to make quite a few misreadings of the demands of the interna-
tional system without suffering serious harm. Nonetheless, the tendency is
for states to respond to their cues.
Here, and at other points throughout the work, Waltz employs analogies
drawn from neoclassical economics, and especially the theory of markets
and the theory of the firm. The pure competitive market is a classical
example of a structure that comes into existence independent of the wishes
of the buyers and sellers who, nonetheless, create it by their actions. Each
individual actor must respond to the signals sent by the market – but ‘must’
in this sense simply means that, say, farmers who attempt to sell at a price
higher than the market will bear will be unable to unload their crops, while
farmers who sell for less than they could get are passing up opportunities
for gain which will be taken up by others who will drive them out of
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business. Similarly buyers will not want to pay more than is necessary and
will not be able to pay less than the going rate. The market structure
emerges out of these decisions, yet the decisions are shaped by the market
structure. The analogy can be taken further. In an uncompetitive market, an
oligopoly, a small number of firms are able to manage prices and output in
such a way that by avoiding direct competition each is better off than they
would otherwise be. These firms have no interest in each other’s survival –
Ford would like to see General Motors disappear and vice versa – but as
profit-maximizers they realize that positive attempts to get rid of the
competition would be far too dangerous to contemplate; a price war might
bring down both firms. In the same way, the United States and the Soviet
Union had a common interest in regulating their competition, even though
each would have preferred the other to disappear had this been achievable
in a riskless, costless way.
It is this economic analogy that might be said to justify the ‘neo’ in ‘neo-
realism’. In effect, and crucially in terms of the influence of his work, Waltz
is offering a ‘rational choice’ version of the balance of power in which states
are assumed to be self-interested egoists who determine their strategies by
choosing that which maximizes their welfare. This is a long way in spirit
from the agonized reliance on the mainspring of the sinfulness of man char-
acteristic of Morgenthau and the ‘righteous realists’ (Rosenthal 1991). In
this respect, he is closer to Carr, whose quasi-Marxist emphasis on scarcity
and the human condition seems to parallel Waltz’s account of anarchy and
the desire for self-preservation. Carr did not adopt a rational choice mode
of theorizing, but even this style of reasoning is not unknown in the classi-
cal tradition. Rousseau’s fable of the stag and the hare is similar in import
to Waltz’s account of the egoism of states: a band of hunters can collectively
meet their needs by bringing down a stag, but at the crucial moment one
leaves the hunt in order to catch a hare, satisfying his individual needs,
but causing the stag to be lost – an excellent illustration of the problems
involved in collective action. Nonetheless, in spite of these predecessors,
there is something new here in the way in which Waltz puts together the
argument.
The extraordinary influence of Waltz’s work can also be seen in the impe-
tus it has given to other scholars to develop structural realist thought, which
has resulted in a conceptual split within the paradigm between ‘defensive’
and ‘offensive’ realists. The two strands of thought agree on the basic
assumption that states’ desire for security is compelled by the anarchic
structure of the international system. However, defensive realists, who
include Stephen Van Evera (1999), Stephen Walt (1987, 2002) and Jack
Snyder (1991) as well as (although not as clearly) Kenneth Waltz, hold that
states attain security by maintaining their position within the system, so
their tendency is towards achieving an appropriate amount of power, in
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balance with other states. Offensive realists, the most influential of whom is
John Mearsheimer (1990, 1994/5, 2001), assert instead that security is so
elusive in a self-help system that states are driven to attain as much power
(defined as material, particularly military, capability) as possible: to become
the global, or at least regional, hegemon. This leads them to pursue aggres-
sive, expansionist policies, argued by offensive realists to be much less
costly and more rewarding than they are seen by defensive realists, who see
such policies as irrational. Defensive realists argue that more power can
lead to less security, therefore that the rational state has little incentive to
seek additional power once it feels secure relative to other powers within
the system. Contrary to offensive realist assumptions, the international
system does not reward states who seek to dominate, but rather those who
maintain the status quo. The main contribution of offensive realism has
been to account for the behaviour of revisionist states which is missing from
Waltzian neorealism.
A further break with Waltzian thought can be seen in the impulse in the
recent work of scholars such as Wohlforth (1993), Schweller (1998) and
Zakaria (1998) to supplement structural neorealism with unit level analysis.
This work, labelled ‘neoclassical’ or ‘postclassical’ realism, contends that
state behaviour cannot be explained using the structural level alone, and
uses the insights of classical realists such as Machiavelli, Morgenthau and
Kissinger in order to reintroduce individual and domestic governmental
level variables (rejected by Waltz in Man, The State and War, 1959) into
explanations of state behaviour in the international system.
Waltz’s neorealism is obviously controversial, but it remains not only the
most convincing restatement of the realist position in recent times, but also
a restatement that links IR theory to the mainstream of (American) political
science. Theory of International Politics is, justly, the most influential book
on International Relations theory of its generation.